Bring a medium saucepan of salted water to a boil. Add beans, return to a boil, and cook until crisp-tender, about 2 minutes. Drain in a colander and rinse under very cold water to stop cooking. Drain again and pat dry.
Heat oil in a large nonstick skillet. Add garlic and cook until softened, about 1 minute. Add beans and zest; cook, stirring occasionally, until beans are warmed through, about 2 minutes. Stir in lemon juice and season to taste with salt and pepper. Serve warm or at room temperature.